Hydrazines and process of preparing same



Patented Apr. 2, 1940 PATENT OFFICE;

2,195,790 HYDRAZINES AND PROCESS .OF PREPARING ,SAM

Max Schmid, Riehen,' Switzerland, assignor to the firm Society ofChemical Industry in Basie,

Basel, Switzerland No Drawing. Application April 26, 1939, Serial No.270,249. In Switzerland April 9; 1938 1 4 Claims.

The present application is a continuation-inpart of my copendingapplication Serial No. 134,452, filed April 1, 1937.

It has been found that new and valuable hydrazine derivatives can beobtained by treat-" ing with acylating agents N-sulfo-derivatives o theformula obtainable by careful reduction of compounds'of the formula soinl i so,H-N-N CH=CH-O-NO2 The new acylated hydrazines correspondtherefore to the general formula H H H which products are valuableintermediate products for the manufacture of dyestuffs, and which intheir free form are light powders which are soluble in water on additionof alkalies and which, when treated with saponifying agents, areconverted into products which. behave on the one hand like aromatichydrazines, since they are converted into pyrazolones with fi-ketoacids, and

on the other hand like amino-compounds of the.

benzene series, since they contain a diazotizable amino-group.

The following examples illustrate the invention, the parts-being byweight:

Example 1 hydrochloric acid of per cent strength and 300' parts of ice.The mixture is then stirred for about 1 hour. The suspension of thediazo compound is allowed to run into a mixture of 39 parts of bisulfiteliquor (40 per' cent of NaI-ISOa) and parts of calcined sodium carbonateat 0-10 C. Stirring is continued for about 12 hours at room the mixturebecomessllghtly acid to congo. This solution is added within 2 hours atabout 85-95 C. to a reducing liquor consisting of 30 parts of ironfilings, 500 parts of Water and 3 parts of acetic acid. Stirring iscontinued for about a further hour and when the reduction is complete,the mixture is made alkaline with 10 parts of calcined sodium carbonate.The whole is filtered hot and allowed to cool to about20 C., whereuponthe solution is made neutral or feebly acid to litmus by addition ofacid, for example hydrochloric acid.

This solution of the 4-amino-4'-hydrazinosulfostilben-Z:2'-disulfonicacid is treated at 0 C.

with 12 parts of acetic acid anhydride. The 4- facetylaminol'-hydrazinosulfo stilben-2z2 di sulfonic' acid thus formedis very easily soluble, so that it can be obtained in solid form best byevaporating the solution in a vacuum. The sodium salt of this acidcorresponds to the-foroHeo O-NH- SO sNa SO aNa It is a light powder veryeasily soluble in water.

By treating this product with sapom'fying agents it can be convertedinto the 4amino-4'-hydrazinestilben-Z:2'-disulfonic acid. Thesubstitution 0 E SOaNa SOzNa v CHa-CHa-CHz-C-N Example 2- 40 parts of4-nitro-4'-aminostilben-2:2'-disulfonic acid are converted into the4-amino-4'-hydrazino-sUlfostilben-2:2-disulfonic acid as indicated inExample 1 by diazotizing, treating with bisulfite solution andreduction. This solution is filtered hot and allowed to cool to about 200., whereupon it is mixed with some ice. At 0-5 C. there are then addedin the course of 1 hour 15.4

parts of benzoyl chloride while stirring well.

Stirring is then continued for about 2 hours. Thee-benzoylaminol-hydrazino-sulfo-stilben- 2:2'-disulfonic acid is partlyprecipitated and separated by salting out after concentration in avacuum. The sodium salt of this acid which corresponds to the formulaSOaNB SO3Na S OaNa S OzNa H What I claim is: 1. Process for themanufacture of hydrazines,

comprising treating N-sulfo-derivatives of the formula S0311 sour withacylating agents.

2. The acylated hydrazines corresponding in the free state to thegeneral formula H H 1 Il $03K soul which products, in the form of theirsodium salts, are light water-soluble powders which, when treated withsaponifying agents, are converted into the product corresponding in thefree state to the general formula S 03H S 0311 3. The acylated hydrazinecorresponding in the free state to the formula ri-Q g r o H a 11 S 0511S 0 H 4. The acylated hydrazine corresponding in the free state to theformula 5 H I a 1'1 MAX SCHMTD.

v CERTIFICATE OF CORRECTIONQ Patent No. 2,195,790. I April 2, 191m.

MAX SCI-MID.

It is hereby certified that error appears in the above number ed patentrequiring correction as follows: In the heading to the printedspecifica- "tion, line 8 thereof, for the foreign filing date "April 9,1958" read April 9, l956-; and that the said Letters Patent should beread with this correction therein that the same may conforrh to 1 therecord of the case in the Patent Office. v

Signed and sealed this 50th day of September, A. D. 1911.1.

Henry Van Arsdale, (Seal) Acting Cormhissioner of Patents.

